Package With Ridged Dome And Methods Of Making And Using The Same

ABSTRACT

The presently disclosed subject matter is directed to a package that allows substantially the entire surface of a product (such as fresh red meat) to be in contact with a desired internal gas concentration. In addition, the disclosed package ensures that large amounts of the product surface are not in contact with the packaging materials to prevent discolored product areas. Particularly, the disclosed package comprises a support member, a thermoformed lidding film, and an oxygen-sensitive product. The lidding film includes one or more ridges that prevent direct contact with the product. As a result, uniform product color is maintained and the product appearance is preserved.

BACKGROUND

Color is an important characteristic of packaged meat products thataffects merchantability. Consumers typically judge the freshness of meatby the presence of the bright red oxymyoglobin pigment. Oxymyoglobin infresh meat decreases with time during storage as it changes tometmyoglobin. Although the pigment loss is primarily cosmetic in nature,it has serious economic consequences. For example, consumers in searchof the freshest looking cuts avoid purchasing meat containing even smallamounts of brown metmyoglobin. The unsold product that results fromoxymyoglobin loss in red meat costs the food industry an estimated $700million dollars annually.

To provide the consumer-preferred red color, meat is commonly packagedin a modified atmosphere package (“MAP”), where it is maintained in asealed pocket containing an atmosphere that is different than ambientair. Packaging fresh meat products with an inert gas atmosphere has beenfound to be an acceptable way to preserve the meat product and providedesirable aging after shipment from a processing facility to a retailoutlet. However, one problem associated with modified atmospherepackages available today is that large areas of the meat surface cancontact an upper barrier film. In such instances, the contacted meatsurface becomes discolored as the meat pigment converts into themetmyoglobin state.

Further, lidding materials composed of two films (a highly permeableinner film and a high barrier outer film) are known in the industry.These prior art lidding films include a small gap positioned between theinner and outer films, filled with a modified atmosphere gas. The highpermeability of the inner film allows the modified atmosphere gas topermeate from the package interior into the gap and then permeate backthrough the inner film to transfer desired gas molecules (i.e., oxygen)to the contacted meat surface. The prior art films therefore can allow ameat product to be in full contact with the permeable inner lidding filmwithout discoloration. Such a system works well for packages with aprofile of up to about 0.5 inches above the flange of a support member.Packaging products with a higher profile often results in the loss ofthe gap between the films. Particularly, either too much tension fromthe product forces the films together or overstretches the inner filmcausing tearing, which makes it impossible to maintain the gap betweenthe films.

The presently disclosed subject matter addresses the shortcomings in theprior art and discloses a package that allows all or substantially allof the surface of a red meat product to be in contact with a desired gasconcentration in high profile geometries. In addition, the disclosedpackage ensures that large amounts of the meat surface are not incontact with the package barrier lidding film, resulting indiscoloration.

The description of the presently disclosed subject matter is discussedherein primarily in relation to meat products. However, it should beappreciated that the presently disclosed subject matter can also beapplied to other oxygen-sensitive foodstuffs and articles to bepackaged.

SUMMARY

In some embodiments, the presently disclosed subject matter is directedto a package comprising a support member and a thermoformed liddingfilm. The support member comprises a lip extending around the perimeterof the support member. The lidding film comprises a flange extendingaround the perimeter of the lidding film and a dome. Specifically, thedome comprises a top and sides that are interconnected to define acavity and a plurality of inwardly-facing ridges disposed on the dometop, sides, or both. The lidding film flange is hermetically sealed tothe lip of the support member to create an enclosed space.

In some embodiments, the presently disclosed subject matter is directedto a method of packaging an oxygen-sensitive product. Particularly, themethod comprises providing a support member comprising a lip extendingaround the perimeter of the support member. The method further comprisesproviding a thermoformed lidding film comprising a flange and a dome.The flange extends around the perimeter of the lidding film. The domecomprises a top and sides that are interconnected to define a cavity anda plurality of inwardly-facing ridges disposed on the top, sides, orboth. The method further comprises providing an oxygen-sensitive productand positioning the product on the support member. In addition, themethod comprises hermetically sealing the lidding film flange to thesupport member lip such that the product is positioned within the cavityand all contact between the lidding film and the product occurs at theridges.

In some embodiments, the presently disclosed subject matter is directedto a method of blooming an oxygen-sensitive product. The methodcomprises providing a support member comprising a lip extending aroundthe perimeter of the support member. The method further comprisesproviding a thermoformed lidding film comprising a flange extendingaround the perimeter of the lidding film and a dome. The dome comprisesa top and sides that are interconnected to define a cavity and aplurality of inwardly-facing ridges disposed on the top, sides, or both.The method comprises providing an oxygen-sensitive product andpositioning the product on the support member. The method furthercomprises inserting a desired atmosphere into the cavity of the packageprior to sealing the lidding film to the support member. In addition,the method comprises hermetically sealing the lidding film flange to thesupport member lip such that all contact between the lidding film andthe product occurs at the ridges. Continuing, the package is eitherwrapped in a barrier overwrap, positioned within a gas barriercontainer, and/or provided with at least one opening covered by aremovable member in the support member or the lidding film. The methodfurther comprises removing the overwrap, gas barrier container, orremovable member at a desired time to initiate blooming of the product.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a is a perspective view of one embodiment of the presentlydisclosed package.

FIG. 1 b is a sectional view taken through line 1 b-1 b of FIG. 1 a.

FIG. 1 c is a perspective view of one embodiment of the disclosedpackage enclosed by a barrier overwrap.

FIG. 1 d is a perspective view of one embodiment of the disclosedpackage enclosed in a gas barrier container.

FIG. 2 a is a top plan view of one embodiment of a disclosed supportmember.

FIG. 2 b is a fragmentary view of one embodiment of a disclosed supportmember.

FIG. 2 c is a fragmentary view of one embodiment of the support memberof FIG. 2 b comprising a product and a lidding film.

FIG. 2 d is one embodiment of a ridged support member in accordance withthe presently disclosed subject matter.

FIG. 2 e is one embodiment of a package in accordance with someembodiments of the presently disclosed subject matter.

FIG. 3 a is a perspective view of one embodiment of a lidding film ofthe disclosed package.

FIG. 3 b is a sectional view taken through line 3 b-3 b of FIG. 3 a.

FIG. 3 c is a sectional view of one embodiment of the disclosed liddingfilm.

FIGS. 4 a-4 c are sectional views of several embodiments of productspositioned on a support member.

FIGS. 5 a-5 c are perspective views of three embodiments of positioninga product on a support member.

FIG. 5 d is a segmented view of one embodiment of a product positionedon a support member.

FIG. 5 e is a perspective view of one embodiment of positioning alidding film on a support member.

FIG. 5 f is a perspective view of one embodiment of a package with alidding film sealed to a support member.

DETAILED DESCRIPTION I. General Considerations

The presently disclosed subject matter is directed to a package thatallows the entire surface (or substantially the entire surface) of anoxygen-sensitive product (such as fresh red meat) to be in contact witha desired internal gas concentration. In addition, the disclosed packageensures that large amounts of the product surface are not in contactwith the packaging materials, which prevents discolored product areasand provides favorable display of the packaged product. FIGS. 1 a and 1b illustrate package 5 comprising support member 10, thermoformedlidding film 15, and red meat product 20. The lidding film isself-supporting and includes one or more ridges 25 positioned about thetop and/or sides that prevent direct contact between the lidding filmand large areas of product 20. As a result, uniform red meat color ismaintained and the meat appearance is preserved (i.e., the meat does notbecome mashed during handling, display, etc.).

II. Definitions

While the following terms are believed to be understood by one ofordinary skill in the art, the following definitions are set forth tofacilitate explanation of the presently disclosed subject matter.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood to one of ordinary skill inthe art to which the presently disclosed subject matter pertains.Although any methods, devices, and materials similar or equivalent tothose described herein can be used in the practice or testing of thepresently disclosed subject matter, representative methods, devices, andmaterials are now described.

Following long-standing patent law convention, the terms “a”, “an”, and“the” can refer to “one or more” when used in the subject specification,including the claims. Thus, for example, reference to “a package”includes a plurality of such packages, and so forth.

Unless otherwise indicated, all numbers expressing quantities ofcomponents, conditions, and so forth used in the specification andclaims are to be understood as being modified in all instances by theterm “about”. Accordingly, unless indicated to the contrary, thenumerical parameters set forth in the instant specification and attachedclaims are approximations that can vary depending upon the desiredproperties sought to be obtained by the presently disclosed subjectmatter.

As used herein, the term “about”, when referring to a value or to anamount of mass, weight, time, volume, concentration, or percentage canencompass variations of, in some embodiments ±20%, in some embodiments±10%, in some embodiments ±5%, in some embodiments ±1%, in someembodiments ±0.5%, and in some embodiments to ±0.1%, from the specifiedamount, as such variations are appropriate in the disclosed system andmethods.

As used herein, the phrase “abuse layer” refers to an outer film layerand/or an inner film layer, so long as the film layer serves to resistabrasion, puncture, and other potential causes of reduction of packageintegrity, as well as potential causes of reduction of packageappearance quality. An abuse layer can comprise any polymer, so long asthe polymer contributes to achieving an integrity goal and/or anappearance goal. In some embodiments, an abuse layer can comprisepolymers having a modulus of at least 10⁷ Pascals, at room temperature.In some embodiments, an abuse layer can comprise (but is not limited to)polyamide and/or ethylene/propylene copolymer, polypropylene; in someembodiments, nylon 6, nylon 6/6, and/or amorphous nylon.

The term “all” as used herein (such as the phrase “all contact”) refersin some embodiments to about 100%. However, the term “all” can refer toamounts of about 80% and higher (i.e., 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99%).

As used herein, the term “antifog film” refers to a polymeric filmhaving at least one surface with properties that have been modified oradapted to have antifog characteristics. That is, the film has atendency to reduce or minimize the negative effects of moisturecondensation. For example, an antifog film can incorporate effectiveamounts one or more antifog agents in the polymeric film resin beforeforming the resin into a film. Further, the antifog film can be alaminated film formed from two films laminated together, in which onefilm has antifog characteristics and the other film does not haveantifog characteristics. Also, the antifog film can be multilayered, inwhich case the antifog agent can be incorporated in one or more of thelayers of the film, such as in one or more of the outer layers of thefilm. The antifog agent can be absent from (i.e., not incorporated in)one or more (or all) of the internal layers of the film. Effectiveamounts of antifog agent in a film layer include from about 0.5% toabout 12%, from about 1% to about 10%, from about 1.5% to about 8%, andfrom about 2% to about 6%, based on the total weight of the layer.Useful amounts of antifog agent in the film include less than about eachof the following: 10%, 5%, 4%, 3%, and 2%, based on the total weight ofthe film.

As used herein, the term “barrier layer”, as applied to films and/orfilm layers, refers to the ability of a film or film layer to serve as abarrier to gases and/or odors. Examples of polymeric materials with lowoxygen transmission rates useful in such a layer can include:ethylene/vinyl alcohol copolymer (EVOH), polyvinylidene dichloride(PVDC), vinylidene chloride copolymer such as vinylidene chloride/methylacrylate copolymer, vinylidene chloride/vinyl chloride copolymer,polyamide, polyester, polyacrylonitrile (available as Barex™ resin), orblends thereof. Oxygen barrier materials can further comprise highaspect ratio fillers that create a tortuous path for permeation (e.g.,nanocomposites). Oxygen barrier properties can be further enhanced bythe incorporation of an oxygen scavenger, such as an organic oxygenscavenger. In some embodiments, metal foil, metallized substrates (e.g.,metallized polyethylene terephthalate (PET), metallized polyamide,and/or metallized polypropylene), and/or coatings comprising SiOx orAlOx compounds can be used to provide low oxygen transmission to apackage. In some embodiments, a barrier layer can have a gas (e.g.,oxygen) permeability of less than or equal to about 500; in someembodiments, less than about 100; in some embodiments, less than about50; and in some embodiments, less than about 25 cc/m²/24 hrs/atm at 73°F. (ASTM D3985).

The term “barrier overwrap” as used herein refers to a material formedfrom a barrier film or material that can cover the external surface ofall or part of a package. In some embodiments, the overwrap can beprovided around a single package; in other embodiments, the overwrap isprovided around a plurality of packages.

The term “bulk layer” as used herein refers to a layer used to increasethe abuse-resistance, toughness, modulus, etc., of a film. In someembodiments, the bulk layer can comprise polyolefin (including but notlimited to) at least one member selected from the group comprising:ethylene/alpha-olefin copolymer, ethylene/alpha-olefin copolymerplastomer, low density polyethylene, and/or linear low densitypolyethylene and polyethylene vinyl acetate copolymers.

The term “dome” as used herein can refer to a rounded shape, including ahemisphere or partial sphere that generally has an elliptic arc or acircular arc-shaped vertical section and horizontal section. It shouldbe appreciated that the term “dome” is not limited to hemisphericalstructures and can include any of a wide variety of shapes or structuresthat enclose a product to be packaged (i.e., rectangular, square, etc.).

As used herein, the phrase “easy open” refers to any unit for accessingthe contents of a package that obviates the need to cut and/or piercethe package with a knife, scissors, or any other sharp implement. Aneasy open feature can be in at least one portion of the web used to forma package and can include one or more cuts, notches, orsurface-roughened areas, lines of structural weakness, or combinationsthereof. Examples of such easy open features are described in U.S.Patent Application Publication Nos. 2005/0084636 to Papenfuss et al. and2005/0254731 to Berbert et al., both of which are incorporated herein intheir entireties. In some embodiments, the easy open feature can includeone or more frangible or peelable layers adapted to manually separate ordelaminate at least a portion of the web used to form the package, asdescribed in U.S. Reissued Pat. No. RE37,171 to Busche et al., which isincorporated herein in its entirety. It will be appreciated that in someembodiments peelable webs can further comprise one or more reclosablepeelable layers. Examples of still other alternative easy open featuresinclude reclosable interlocking fasteners attached to at least a portionof the web used to form the package. Reclosable fasteners, in general,are known and are taught, for example, in U.S. Pat. Nos. 5,063,644;5,301,394; 5,442,837; 5,964,532; 6,409,384; 6,439,770; 6,524,002;6,527,444; 6,609,827; 6,616,333; 6,632,021; 6,663,283; 6,666,580;6,679,027; and U.S. Patent Application Nos. 2002/0097923; and2002/0196987, all hereby incorporated by reference in their entireties.

As used herein, the term “film” includes, but is not limited to, alaminate, sheet, web, coating, and/or the like, that can be used topackage a product. The film can be a rigid, semi-rigid, or flexibleproduct, and can be adhered to a non-polymeric or non-thermoplasticsubstrate such as paper or metal to form a rigid, semi-rigid, orflexible product or composite.

The term “gas barrier container” refers to an oxygen-impermeable bag,envelope, or other like container that can house one or more packages.The gas barrier container includes an interior and a closure mechanism(which can include any of a wide variety of zippers, seals, fasteners,and the like known in the art). After a product is inserted into thecontainer interior, the container can be closed or sealed for a desiredamount of time. In some embodiments, before the container is sealed, apreferred gaseous environment (low oxygen or high oxygen concentrations,for example) can be inserted into the container interior.

As used herein, the term “lidding film” comprises any of a wide varietyof films that can be fitted or sealed to a support member to generate anenclosed space. For example, in some embodiments, the lidding film cancomprise a thermoformed film with a flange that is bonded to a supportmember.

As used herein, the terms “MAP” and/or “modified atmosphere package”refer to a packaging format wherein a gas is actively flushed into theheadspace of a package prior to sealing. In general, the gas is modifiedto be different from that normally found in the atmosphere outside theMAP. The result is a package with a considerable volume of gassurrounding the viewing surface of a packaged product. An example ofsuch a package is disclosed in, e.g., U.S. Pat. No. 5,686,126 to Noel etal., the entire disclosure of which is hereby incorporated by reference.

The term “meat” refers to any myoglobin-containing orhemoglobin-containing tissue from an animal, such as beef, pork, veal,lamb, mutton, chicken, turkey, venison, quail, and duck. The meat can bein a variety of forms including primal cuts, subprimal cuts, and/orretail cuts as well as ground, comminuted, or mixed. The meat or meatproduct is preferably fresh, raw, uncooked meat, but can also be frozen,hard chilled, or thawed. In some embodiments, the meat can be subjectedto other irradiative, biological, chemical and/or physical treatments.The suitability of any particular such treatment can be determinedwithout undue experimentation in view of the present disclosure.

As used herein, the term “oxygen impermeable” refers to the ability of afilm or layer to serve as a barrier to one or more gases (i.e., gaseousO₂). Such barrier materials can include (but are not limited to)ethylene/vinyl alcohol copolymer, polyvinyl alcohol homopolymer,homopolymer and copolymer of polyvinylidene chloride, polyalkylenecarbonate, polyamide, polyethylene naphthalate, polyester,polyacrylonitrile, polyvinyl chloride (when bonded to a barrier film),homopolymer and copolymer, liquid crystal polymer, SiOx, carbon, metal,metal oxide coated films, and the like, as known to those of ordinaryskill in the art. In some embodiments, the oxygen-impermeable film hasan oxygen transmission rate of no more than 100 cc/m²/day/atm; in someembodiments, less than 50, 25, 10, 5, or 1 cc/m²/day/atm (tested at 1mil thick and at 25° C. in accordance with ASTM D3985).

As used herein, the term “oxygen permeable” refers to a film packagingmaterial that can permit the transfer of oxygen from the exterior of thefilm (i.e., the side of the film in contact with the outsideenvironment) to the interior of the film (i.e., the side of the film incontact with the internal package environment). In some embodiments,“oxygen permeable” can refer to films or layers that have a gas (e.g.,oxygen) transmission rate of at least about 1,000; 5,000; 10,000;50,000; or 100,000 cc/m²/24 hrs/atm (at 73° F. in accordance with ASTMD3985). The term “permeable” can also refer to films that do not havesuch high gas permeability, but that are sufficiently permeable toaffect a sufficiently rapid bloom for the particular product andparticular end use application.

The term “oxygen sensitive” as used herein refers to the ability of aproduct to react with oxygen. The term includes products that oxidize inthe presence of oxygen, such as whole grains, fruit, and the like. Theterm also includes products such as fresh red meat that bloom in thepresence of oxygen.

The term “oxygen transmission rate” is measured according to ASTM D3985,a test known to those of ordinary skill in the art, and which is herebyincorporated by reference in its entirety. Further, all ASTMs referencedherein are incorporated by reference in their entireties.

As used herein, the term “package” refers to an object of manufacturethat can be in the form of a web (e.g., monolayer or multilayer films,monolayer or multilayer sheets), bag, shrink bag, pouch, casing, tray,lidded tray, overwrapped tray, shrink package, vacuum skin package, flowwrap package, thermoformed package, packaging insert, or combinationsthereof. It will be appreciated by those skilled in the art that suchpackages can include flexible, rigid, or semi-rigid materials and can beheat shrinkable or non-heat shrinkable, oriented or non-oriented. Insome embodiments, a package can include a support member and a domedlidding film.

The term “permeable member” includes any of a wide variety of permeableelements known in the art, including (but not limited to) permeablepolymeric films, open netting materials, barrier or non-barriermaterials with one or more openings or perforations, open weavematerials, fabrics, and the like. In some embodiments, the permeablemember can have a gas (e.g., oxygen) transmission rate of at least about1,000; 5,000; 10,000; 50,000; or 100,000 cc/m²/24 hrs/atm (at 73° F. inaccordance with ASTM D3985).

As used herein, the term “polymer” (and specific recited polymers) referto the product of a polymerization reaction, and is inclusive ofhomopolymers, copolymers, terpolymers, etc.

As used herein, the term “polymerization” can be inclusive ofhomopolymerizations, copolymerizations, terpolymerizations, etc., andcan include all types of copolymerizations such as random, graft, block,etc. In general, the polymers in the films of the presently disclosedsubject matter can be prepared in accordance with any suitablepolymerization process, including slurry polymerization, gas phasepolymerization, high pressure polymerization processes, and the like.

The term “removable member” as used herein refers to any of a widevariety of labels, stickers, tags, coated paper, and the like that canbe removably adhered to the disclosed package (i.e., over an opening).The removable member can be attached to the package by adhesives, heatsealing, and/or other methods well known in the packaging art. As wouldbe appreciated, the removable member can be oxygen permeable or oxygenimpermeable.

As used herein, the term “ridge” refers to any of a wide variety ofdownward-extending (i.e., toward the packaged product) elements integralto a lidding film of the disclosed package, including (but not limitedto) projections, valleys, channels, protrusions, grooves, pyramids,facets, indentations, and the like. The ridges can be linear ornon-linear. In addition, the ridges can be uniformly distributed ornon-uniformly distributed about the top and/or sides of the liddingfilm. In some embodiments, the ridges can further be distributed on thesurface of the support member. The ridges can be of uniform width anddepth or can vary with respect to the width and depth depending onlocation.

As used herein, the term “seal” refers to any bond between a firstregion of a film surface to a second region of a film surface. In someembodiments, a seal can be formed by heating an area to the sealinitiation temperature (often with applied pressure) to weld respectivefilm surfaces together. In some embodiments (such as modified atmospherepackages), the seal can be a hermetic seal. The heat sealing can beperformed by any one or more of a wide variety of manners, such as usinga heated bar, hot air, infrared radiation, radio frequency radiation,etc.

As used herein, the phrases “seal layer”, “sealing layer”, “heat seallayer”, and “sealant layer”, refer to an outer film layer, or layers,involved in the sealing of the film to itself, another film layer of thesame or another film, and/or another article that is not a film. Itshould also be recognized that in general, up to the outer 3 mils of afilm can be involved in the sealing of the film to itself or anotherlayer. With respect to packages having only fin-type seals, as opposedto lap-type seals, the phrase “sealant layer” generally refers to theinside film layer of a package, as well as supporting layers adjacentthis sealant layer often being sealed to itself, and frequently servingas a food contact layer in the packaging of foods. In general, a sealantlayer sealed by heat-sealing layer comprises any thermoplastic polymer.In some embodiments, the heat-sealing layer can comprise, for example,thermoplastic polyolefin, thermoplastic polyamide, thermoplasticpolyester, and thermoplastic polyvinyl chloride. In some embodiments,the heat-sealing layer can comprise thermoplastic polyolefin.

The term “support member” as used herein refers to a component of thedisclosed package onto which a packaged product is directly orindirectly placed. In some embodiments, a support member can include lipor flange that provides a sealing surface for attachment of a liddingfilm with a cavity to thereby receive and enclose the product within thecavity.

As used herein, the term “thermoforming” comprises vacuum formingwherein a preheated softened sheet is disposed on a molding portionhaving the shape of a desired product, and the air present in the gapbetween the molding portion of the molding die and the sheet iseliminated by pulling vacuum so that the sheet conforms to the contoursof the mold. The term “thermoforming” can also comprise air pressureassist molding with jointly used vacuum forming and pressure formingwherein a sheet is contacted with the molding portions by compressed airat a pressure that is not less than atmospheric pressure. Further, theterm can include match mold assist forming in which a plug matching theinternal shape of the mold is used to guide the deformation of thesheet. See, for example, U.S. Pat. Nos. 4,192,699; 4,576,669; 4,735,855;5,350,622; and 5,529,833, the entire disclosures of which areincorporated by reference herein.

As used herein, the term “tie layer” refers to an internal film layerhaving the primary purpose of adhering two layers to one another. Insome embodiments, tie layers can comprise any nonpolar polymer having apolar group grafted thereon, such that the polymer has affinity fornonpolar polymers such as polyethylene and is also capable of covalentbonding to polar polymers such as polyamide and ethylene/vinyl alcoholcopolymer. In some embodiments, tie layers can comprise at least onemember selected from the group including, but not limited to, modifiedpolyolefin, modified ethylene/vinyl acetate copolymer, and/or modifiedhomogeneous ethylene/alpha-olefin copolymer. In some embodiments, tielayers can comprise at least one member selected from the groupconsisting of anhydride modified grafted linear low densitypolyethylene, anhydride grafted low density polyethylene, anhydridegrafted homogeneous ethylene/alpha-olefin copolymer, and/or anhydridegrafted ethylene/vinyl acetate copolymer.

The term “vacuum skin packaging” or “VSP” as used herein refers to aprocess wherein a thermoformable film (i.e., capable of being formedinto a desired shape upon the application of heat) is thermoformed abouta product on a tray by means of heat and/or pressure. Virtually all ofthe air is evacuated from a predefined space around the packaging filmso that when the film is attached to the tray about the product and theresultant package is subsequently exposed to atmospheric pressure, thefilm conforms very closely to the contour of the packaged product.Further details are described in U.S. Pat. No. RE 30,009 to Purdue etal.; U.S. Pat. No. 5,346,735 to Logan et al.; and U.S. Pat. No.5,770,287 to Miranda et al., the disclosures of which are incorporatedby reference herein.

Any compositional percentages used herein are presented on a “by weight”basis, unless designated otherwise.

Although the majority of the above definitions are substantially asunderstood by those of skill in the art, one or more of the abovedefinitions can be defined hereinabove in a manner differing from themeaning as ordinarily understood by those of skill in the art, due tothe particular description herein of the presently disclosed subjectmatter.

III. The Disclosed Package III.A. Generally

As set forth herein, package 5 includes support member 10, thermoformedlidding film 15, and product 20. As illustrated in the Figures, supportmember 10 is generally a “bottom” member (i.e., in normal usage, thepackage will rest on the support member). Likewise, lidding film 15 isgenerally a “top” member (i.e., in normal usage, the package will bepositioned such that the lidding film comprises the top of the package).Nevertheless, those skilled in the art will understand after a review ofthe presently disclosed subject matter that package 5 can bemanufactured, stored, shipped, and/or displayed in any suitableorientation.

The films used to construct support member 10 and lidding film 15 can bemonolayer or multilayer. Typically, however, the films employed willhave two or more layers to incorporate a variety of properties, such assealability, gas impermeability, and toughness into a single film. Thus,in some embodiments, support member 10 and/or lidding film 15 comprise atotal of from about 4 to about 20 layers; in some embodiments, fromabout 4 to about 12 layers; and in some embodiments, from about 5 toabout 9 layers. Accordingly, the disclosed films can comprise 1, 2, 3,4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 layers.One of ordinary skill in the art would also recognize that the disclosedfilms can comprise more than 20 layers, such as in embodiments whereinthe films comprise microlayering technology.

Support member 10 and lidding film 15 can have any total thicknessdesired, so long as they provide the desired properties for theparticular packaging operation used, e.g., optics, modulus, sealstrength, and the like. Final web thicknesses can vary, depending onprocess, end use application, and the like. Typical thicknesses canrange from about 0.1 to 25 mils; in some embodiments, about 0.5 to 20mils; in some embodiments, about 1 to 18 mils; in some embodiments,about 3 to 15 mils; in some embodiments, about 5 to 12 mils; and in someembodiments, about 8 to 10 mils.

Suitable materials from which support member 10 and/or lidding film 15can be constructed include (without limitation) polyvinyl chloride,vinylidene chloride copolymer, nylon, polyethylene terephthalate,ethylene/vinyl alcohol copolymer, polyethylene terephthalate,polystyrene, high impact polystyrene, polyolefins such as high densitypolyethylene or polypropylene, copolymers of polypropylene,polyurethane, polyester, copolyester, polybutylene terephthalate,styrene-butadiene copolymers, polyacrylonitrile copolymers,polycarbonate, polymethylmethacrylate, polyethylene terphthalate,crystalline polyethylene terphthalate, amorphous polyethyleneterephthalate, polyamides, polylactic acid, polyhydroxyalkanoates, orcombinations thereof.

Thus, support member 10 and lidding film 15 can be constructed from anyof a wide variety of polymeric films that can comprise one or morebarrier layers, seal layers, tie layers, abuse layers, and/or bulklayers. The polymer components used to fabricate support member 10 andlidding film 15 can also comprise appropriate amounts of other additivesnormally included in such compositions. For example, slip agents (suchas talc), antioxidants, fillers, dyes, pigments and dyes, radiationstabilizers, antistatic agents, elastomers, and the like can be added tothe disclosed films. See, for example, U.S. Pat. No. 7,205,040 toPeiffer et al.; U.S. Pat. No. 7,160,378 to Eadie et al.; U.S. Pat. No.7,160,604 to Ginossatis; U.S. Pat. No. 6,472,081 to Tsai et al.; U.S.Pat. No. 6,222,261 to Horn et al.; U.S. Pat. No. 6,221,470 to Ciocca etal.; U.S. Pat. No. 5,591,520 to Migliorini et al.; and U.S. Pat. No.5,061,534 to Blemberg et al., the disclosures of which are herebyincorporated by reference in their entireties.

The films used to form support member 10 and lidding film 15 can beconstructed using any suitable process known to those of ordinary skillin the art, including (but not limited to) coextrusion, lamination,thermoforming, extrusion coating, and combinations thereof.

In some embodiments, at least a portion of support member 10 and/orlidding film 15 can be irradiated to induce crosslinking. In theirradiation process, a film is subjected to one or more energeticradiation treatments, such as corona discharge, plasma, flame,ultraviolet, X-ray, gamma ray, beta ray, and high energy electrontreatment, each of which induces cross-linking between molecules of theirradiated material. The irradiation of polymeric films is disclosed inU.S. Pat. No. 4,064,296, to Bornstein at al., which is herebyincorporated by reference in its entirety.

In some embodiments, support member 10 and/or lidding film 15 can haveoxygen transmission barrier attributes, particularly when product 20 isan oxygen-sensitive food product (such as fresh red meat). In theseembodiments, support member 10 and/or lidding film 15 can have athickness and composition sufficient to provide an oxygen transmissionrate of no more than about any of the following values: 1000, 500, 150,100, 50, 45, 40, 35, 30, 25, 20, 15, 10, and 5 cc/m²-day-atm, measuredat 0% relative humidity and 23° C. (ASTM D-3985).

Alternatively, support member 10 and/or lidding film 15 can be oxygenpermeable in some embodiments. In these embodiments, support member 10and/or lidding film 15 can have a permeability of greater than about10,000; in some embodiments, greater than about 15,000; and in someembodiments, greater than about 17,000 cc/m²-day-atm at 73° C. (ASTMD-3985). In these embodiments, package 5 can optionally comprise barrieroverwrap 110 that completely or partially covers the package and adheresor clings to itself or to the package, as illustrated in FIG. 1 c. See,for example, U.S. Pat. No. 6,408,598 to Stockley; U.S. Pat. No.5,663,002 to Schirmer; U.S. Pat. No. 4,759,444 to Barmore; U.S. Pat. No.5,018,623 to Hrenyo; and U.S. Pat. No. 5,503,858 to Reskow, the entiredisclosures of which are incorporated herein by reference.Alternatively, in some embodiments, package 5 can be inserted into gasbarrier container 115 such that the package is completely enclosed andsealed within, as shown in FIG. 1 d. In some embodiments, the barriercontainer can be evacuated of normal atmosphere and flushed with apreservation-enhancing gas (such as, for example, CO₂) and then sealed.See, for example, U.S. Pat. No. 6,716,499 to Vadhar; U.S. Pat. No.6,544,660 to Lind; U.S. Pat. No. 4,755,402 to Oberle; and U.S. Pat. No.4,716,061 to Winter, the entire disclosures of which are incorporatedherein by reference.

In some embodiments, support member 10 and/or lidding film 15 aretransparent (at least in the non-printed regions) such that product 20is visible. The term “transparent” as used herein can refer to theability of a material to transmit incident light with negligiblescattering and little absorption, enabling objects (e.g., packaged foodor print) to be seen clearly through the material under typical unaidedviewing conditions (i.e., the expected use conditions of the material).The transparency of the film can be at least about any of the followingvalues: 20%, 25%, 30%, 40%, 50%, 65%, 70%, 75%, 80%, 85%, and 95%, asmeasured in accordance with ASTM D1746.

III.B. Support Member 10

FIG. 2 a illustrates support member 10 configured as a flat, planarportion of film. The support member includes product support surface 25for receiving and supporting the product being packaged and lip 30 towhich the lidding film is sealed. In some embodiments, lip 30 comprisesthe outer edges of the support member (i.e., extending away from center35). Although support member 10 can be a flat, planar portion of film,in some embodiments it can be configured as a tray and the like, aswould be known in the art.

For example, as illustrated in FIG. 2 b, in some embodiments supportmember 10 can be thermoformed to include at least one depression 31sized to accept and secure product 20. In these embodiments, thedepression can be concave to accommodate product 20 and optionally asoaker pad or other similar device. As illustrated in FIG. 2 c, supportmember 10 can be configured such that package 5 includes separation 32which ensures that the product sides are not in contact with the sidewall of the lidding film. Separation 32 further allows the inner packageatmosphere to contact the sides of product 20. Depression 31 furtherallows product 20 to remain relatively stationary in the package undernormal handling and shipping conditions.

Support member 10 can be rigid, semi-rigid, or flexible. For example,the support member can have a 1% secant flex modulus of at least aboutany of the following values: 120,000; 140,000; 160,000; 180,000;200,000; 225,000; or 250,000 pounds/square inch (in accordance with ASTMD-790).

In some embodiments, support member 10 (and/or lidding film 15) cancomprise an easy open feature, such as tab 40, depicted in FIG. 2 a. Inuse, one would merely peel tab 40 to separate support member 10 fromlidding film 15 to have direct access to the packaged product.Alternatively or in addition, in some embodiments, package 5 cancomprise an easy peel seal on either the support member or the liddingfilm to allow the package to be opened and the product dispensed withoutthe end user touching the product. As would be appreciated by those ofordinary skill in the art, a peel seal easily pulls apart withoutrupturing either film. One of ordinary skill in the art would alsorecognize that any of a number of suitable openings can be includedwithin the presently disclosed subject matter. For example, ring pulltabs, zippers, and the like can be used. See, for example, U.S. Pat. No.7,419,301 to Schneider et al.; U.S. Pat. No. 7,395,642 to Plourde etal.; U.S. Pat. No. 7,322,920 to Johnson; U.S. Pat. No. 7,261,468 toSchneider et al.; U.S. Pat. No. 6,539,691 to Beer; U.S. Pat. No.5,121,997 to La Pierre et al.; U.S. Pat. No. 5,100,246 to La Pierre etal.; U.S. Pat. No. 5,077,064 to Hustad et al.; U.S. Pat. No. 5,022,530to Zieke; U.S. Pat. No. 6,976,588 to Wischusen et al.; U.S. Pat. No.5,865,335 to Farrell et al.; U.S. Pat. No. 5,332,150 to Poirier; U.S.Pat. No. 4,778,059 to Martin et al.; and U.S. Pat. No. 4,680,340 toOreglia et al., the entire disclosures of which are incorporated hereinby reference.

In some embodiments, the bottom and/or sides of support member 10 caninclude one or more ridges 25, as illustrated in FIG. 2 d. In theseembodiments, product 20 (red meat, for example) contacts the supportmember at the ridges such that the majority of the product surface is incontact with the gaseous environment of the package interior. As aresult, the bottom surface of the meat product maintains a desired colorat the time of display.

Although the support members illustrated in the enclosed Figures depicta single product 20, the presently disclosed subject matter can includea support member (and/or lidding film) formed with one or more areas tohouse a plurality of products. For example, FIG. 2 e illustrates oneembodiment of package 5 comprising first and second package areas 45, 50that each houses a packaged product. The compartments can be separatedat any desired time by tearing along a line of weakness (such as alongperforations 55), or cutting, ripping, and the like.

Support member 10 can have any desired configuration or shape, such ascircular, oval, square, rectangular, polygonal, hexagonal, etc. In someembodiments, the shape of the support member can be dictated by theshape of the lidding film and/or the packaged product.

In the case of red meat or other similar products that can includeliquids of any type, the material used to construct support member 10can be comparably dense to prevent seepage of the liquid. Absorbenttrays such as those supplied by Vitembal (Avignon, France) or Linpak(Swanton, Ohio, United States of America) can be employed for thispurpose. Alternatively or in addition, in some embodiments, supportmember 10 can comprise an absorbent pad to absorb product drip loss andto further prevent or reduce discoloration of product 20. Examples ofsuch absorbent pads are provided in U.S. Pat. Nos. 5,320,895 and6,278,371, the entire disclosures of which are incorporated herein byreference.

III.C. Product 20

Product 20 can be positioned on support surface 25 of support member 10using any method known in the art. Product 20 can include any of a widevariety of food products including (but not limited to) vegetables,fruit, pasta, poultry (including chicken, duck, goose, turkey, and thelike), buffalo, camel, cow, dog, game (including deer, eland, antelope,and the like), game birds (such as pigeon, quail, doves, and the like),goat, hare, horse, kangaroo, lamb, marine mammals (including whales andthe like), amphibians (including frogs and the like), monkey, pig,rabbit, reptiles (including turtles, snakes, alligators, and the like),and/or sheep. One of ordinary skill in the art would readily recognizethat the above list is not exhaustive.

In addition, product 20 can include any of a wide variety of non-fooditems including (but not limited to) pharmaceuticals, photographic film,computer components, inorganic materials susceptible to oxidation,electronics, biological systems, and the like. One of ordinary skill inthe art would readily recognize that the above list is not exhaustiveand can include any of a variety of non-food items.

III.D. Lidding Film 15

As set forth herein above, package 5 comprises lidding film 15 which canbe fitted to top surface 25 of support member 10. The lidding film canbe configured as a transparent thermoformed dome that has theappropriate geometry to keep product 20 from contacting large continuousareas of the lidding film. As a result, the outer surface of thepackaged product is in contact with gaseous environment of the packageinterior. As illustrated in FIGS. 3 a and 3 b, lidding film 15 comprisesflange 60. Further, top 80 and sides 85 form convex dome 65 positionedabove the flange. The flange outwardly extends with respect to the domeand includes dimensions that can approximate the dimensions of supportmember lip 30. Thus, when lidding film 15 engages support member 10,flange 60 is sealed to (or mates with) the support member lip to providea hermetic seal about the periphery of package 5.

Dome 65 extends upwardly from the edges of flange 65 to form enclosedcavity 70 that houses product 20. In some embodiments, the size andshape of dome 65 approximates the size and shape of product 20. Asdepicted in FIGS. 3 a and 3 b, dome sides 85 and/or top 80 comprise aplurality of ridges 75 that extend inward (i.e., toward product 20) toprevent contact between large areas of the product and lidding film 15.Ridges 75 can extend horizontally, vertically, diagonally, or in anysuitable direction or orientation. Thus, product 20 at most contactsridges 75 instead of the entire surface of the lidding film top 80and/or sides 85. As a result, product 20 is not adversely affected(i.e., in the case of fresh red meat, the meat surface remains brightred in color and is not substantially altered in appearance).

In some embodiments, lidding film 15 can be coated or sprayed with aneffective amount of an antifog agent on its interior surface (i.e., thesurface facing product 20). See, for example, U.S. Pat. No. 5,451,460and PCT International Publication No. WO/99/00250, both of which areincorporated herein in their entireties. Alternatively or in addition,in some embodiments, lidding film 15 can be constructed from an antifogfilm or from a material comprising one or more antifog agents. Suitableantifog agents are known in the art. See, for example, U.S. Pat. No.7,608,312, the entire content of which is hereby incorporated byreference.

In some embodiments, lidding film 15 (and/or support member 10)comprises one or more openings 90 that allow the influx of atmosphericair into enclosed cavity 70 (i.e., into the interior of the package) ata desired time, such as at the time of retail display. In someembodiments, openings 90 are covered by a label or other removablemember 95 that is removed on demand, as illustrated in FIG. 3 c. Forexample, in embodiments wherein the interior cavity of package 5 isflushed with carbon monoxide and/or product 20 is pre-treated withcarbon monoxide, removable member 95 can be disconnected from thepackage to allow the carbon monoxide gas to exit the package interior.In addition, oxygen from the ambient atmosphere is allowed into thepackage interior through openings 90. As would be appreciated by thoseof skill in the packaging art, the meat begins to lose its bright redcolor as the carbon monoxide is replaced by atmospheric oxygen. Thecolor change offers end users a good visual indicator of dated product.

III.E. Permeable Member 100

In some embodiments, package 5 optionally comprises permeable member 100positioned between product 20 and lidding film 15 (i.e., covering thesurface of the product). Permeable member 100 can be any of a widevariety of items that are permeable to oxygen, including (but notlimited to) permeable films, open netting materials, and the like.Permeable member 100 prevents the transfer of product 20 to the liddingfilm, which would thereby reduce visibility of the packaged product. Forexample, when product 20 is fresh red meat, member 100 prevents thetransfer of grease and/or fat onto lidding film 15. Thus, because thepermeable member stays in contact with the meat surface, any greasetransfer that occurs will not be visible.

Permeable member 100 can be attached or unattached to support member 10and lidding film 15. For example, in some embodiments, product 20 can bepackaged in permeable member 100 using a flow wrap-type machine withseals, partial seals, or no seals, as illustrated in FIG. 4 a. Thewrapped product can then optionally be vacuumized in a chamber machinethat has no seal bars prior to positioning on support member 10.Alternatively, in some embodiments, permeable member 100 can simply bedraped over product 20, as illustrated in the embodiment of FIG. 4 b. Asdepicted in FIG. 4 c, in some embodiments, permeable member 100 can besealed or attached to support member 10 using methods well known in theart (such as heat sealing, adhesives, mechanical closures, and thelike).

IV. Methods of Making the Disclosed Package

As illustrated in FIG. 5 a, product 20 is positioned on surface 25 ofsupport member 10 using any of a variety of methods known to those ofordinary skill in the art. For example, product 20 can be manually ormechanically placed on center area 35 of the support member. Optionally,product 20 can be covered by permeable member 100 either beforeplacement onto support member 10 (FIG. 5 b) or after placement ontosupport member 10 (FIG. 5 c).

As illustrated in FIG. 5 d, in some embodiments, package 10 can be ahigh profile package. See, for example, U.S. Pat. No. 8,357,414, theentire content of which is hereby incorporated by reference. In theseembodiments, product 20 extends to a height 21 at least 0.75 inchesabove support member height 22. Thus, in some embodiments, product 20can extend to a height 21 at least 0.75, 1, 1.25, 1.5, 1.75, 2, 2.25,2.5, 2.75, 3, 3.25, 3.5, 3.75, 4, 4.25, 4.5, 4.75, or 5 inches above thesupport member. Similarly, in some embodiments, the ratio of height 21to height 22 is at least about 0.01:1, 0.05:1, 0.1:1, 0.25:1, 0.5:1,0.75:1, 1:1, 1.25:1, 1.5:1, 1.75:1, 2.0:1, 2.25:1, 2.5:1, 2.75:1, 3.0:1,3.25:1, 3.5:1, 3.75:1, 4.0:1, 4.25:1, 4.5:1, 4.75:1, 5.0:1, 5.25:1,5.5:1, 5.75:1, 6.0:1, 6.25:1, 6.5:1, 6.75:1, 7.0:1, 7.25:1, 7.5:1,7.75:1, 8.0:1, 8.25:1, 8.5:1, 8.75:1, 9.0:1, 9.25:1, 9.5:1, 9.75:1, or10:1. It should be appreciated that height 21 (and the ratio of height21 to 22) can be more or less than the range set forth herein. Consumersin some areas prefer high profile packages to enable them to view largeareas of the product.

Once product 20 is deposited onto support member 10, lidding film 15 canbe sealed to the support member to create a closed package, asillustrated in FIG. 5 e. Particularly, flange 60 of the lidding film issealed to lip 30 of the support member to enclose product 20 withincavity 70, as shown in FIG. 5 f. The resulting seal 105 can extendcontinuously around the outer perimeter (i.e., outer edge) of thesupport member to hermetically seal and enclose product 20. Thus,package 5 can be sealed on all edges using conventional means (i.e.,adhesive, heat sealing, and the like).

In some embodiments, the sealing operation can occur at a food packagingplant using a heat sealing machine designed for high speed operation.Heat sealing can occur via any of a number of techniques well known inthe art, such as but not limited to, thermal conductance heat sealing,impulse sealing, ultrasonic sealing, dielectric sealing, and/orcombinations thereof. Other forms of sealing can be used as appropriate,including pressure sensitive adhesives, ultrasonic sealing, mechanicalclosures, and/or interlocking members. Lidding film 15 and supportmember 10 therefore form an enclosure for product 20 that protects theproduct from contact with the surrounding environment including dirt,dust, moisture, microbial contaminants, and optionally ambient air,especially when product 20 is a food product.

In some embodiments, construction of package 5 can also include the stepof admitting a desired gas into cavity 70 immediately prior tohermetically sealing lidding film 15 to support member 10. In theseembodiments, lidding film 15 and support member 10 are constructed fromoxygen impermeable materials and/or are surrounded by a barrier overwrapor gas barrier container. Thus, in some embodiments, package 5 can be amodified atmosphere package (“MAP”), wherein product 20 is maintainedwithin the interior of the package with an atmosphere that is differentthan ambient air. For example, fresh meat and other food products can bepackaged in a low-oxygen environment (e.g., high levels of carbondioxide and/or nitrogen) after evacuating all or most of the air fromthe package. Such MAP systems are well known to those of ordinary skillin the art. Examples of such MAP packaging are disclosed in U.S. Pat.No. 5,686,126 to Noel et al. and U.S. Pat. No. 5,779,050 to Kocher etal., the entire disclosures of which are hereby incorporated byreference. In some embodiments, the internal gas pressure can beatmospheric pressure, nominal atmospheric pressure, or slightly elevatedgas pressure, as can be appreciated by those of ordinary skill in theart. It should be noted that the presently disclosed subject matter alsocomprises embodiments wherein package 5 is not a modified atmospherepackage and the interior of the article comprises ambient air.

Thus, in some embodiments, the oxygen level within the interior ofpackage 5 can be reduced to a level in the range of less than about 0.5weight %; in some embodiments, less than about 0.1 weight %; and in someembodiments, less than about 0.05 weight %, based on the total weight ofthe air within the enclosed package cavity. The reduction in oxygenlevel can be accomplished using one or more techniques, including (butnot limited to) evacuation, gas flushing, and/or oxygen scavenging. Suchmethods are well known to those of ordinary skill in the packaging art.In some embodiments, the modified atmosphere can include carbonmonoxide, which reacts with red meat to create a bright red color withno oxygen present. Package 5 is then sealed to provide an airtight,sealed container containing an internal low-oxygen atmosphere. Themodified package can then be stored in a refrigeration unit for severalweeks prior to being offered for sale at a retail establishment.

Another type of MAP employs a high-oxygen internal environment for freshred meat or poultry. In these embodiments, ambient air is evacuated fromthe interior of package 5 and replaced with a high-oxygen environment(i.e., about 80% oxygen and about 20% carbon dioxide). Thus, forexample, in some embodiments the interior of the modified atmospherepackage can include at least about 50%, 55%, 60%, 65%, 70%, 75%, 80%,85%, 90%, or 95% oxygen. In some embodiments, the package furthercomprises at least about 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or50% carbon dioxide. The high-oxygen environment preserves the meat andmaintains the desirable bright red color for a period of about 14 days.

V. Methods of Using the Disclosed Package

As discussed herein above, package 5 can be shipped to a retaildistributor in the embodiment depicted in FIG. 1 a. Particularly,product 20 can be enclosed within the interior of a package, betweensupport member 10 and lidding film 15. In some embodiments, the packageis a modified atmosphere package, wherein the interior of the packagehas a different environment compared to ambient air. Alternatively or inaddition, the meat can be pre-treated with a desired gas (such as carbonmonoxide) prior to insertion onto the support member. The final step (orone of the final steps) in a packaging method according to the presentlydisclosed subject matter is to allow ambient air into the cavity of thepackage. For example, in some embodiments, removable member 95 can bedisconnected from lidding film 15 or support member 10 to expose opening90 that enables atmospheric oxygen to enter into the package interior.In the case of red meat products, for example, upon exposure to theincreased oxygen concentration, the meat will bloom to a red color,which is pleasing to consumers.

In embodiments wherein package 5 is packaged within barrier overwrap 110or gas barrier container 115, a user simply removes the package from theoverwrap or gas barrier container. In these embodiments, support member10 and/or lidding film 15 are constructed from permeable materials, suchthat ambient air is allowed to flow into the package interior to contactproduct 20.

Alternatively or in addition, a physical opening can be created in thepackage, such as by the retailer breaching the integrity of the supportmember or lidding film (e.g. a knife cut, punched hole, etc.), though itis generally preferably that the package remains sealed. Further,package 5 can in some embodiments comprise openable and closeable valvemembers to admit ambient air into the package interior on demand. Suchvalve members are well known in the packaging art.

VI. Advantages of the Disclosed Package

The presently disclosed package allows the viewing surface of a productto be in constant contact with a desired gas concentration. In case offresh red meat, for example, the package displays a product thatexhibits a bright red color as desired for commercial sale.

Further, the disclosed package solves the problem of how to preventrelatively large areas of the packaged product from being in directcontact with a barrier film. In the case of fresh red meat, for example,contact with a barrier film results in a discolored area on the meat dueto inadequate contact with the interior package gas. By minimizingcontact between the lidding film and large areas of the meat, the redcolor of the meat is maintained, which has proved to be desirable toconsumers. In addition, the areas of grease transfer from the product tothe lidding film are minimized.

The disclosed package also enables a large percentage of the packagedproduct to be visible, compared to prior art packages (such as fresh redmeat packages wrapped in a barrier overwrap, for example). The highvisibility results from the high profile and favorable opticalproperties provided by the convex lidding film.

Continuing, the disclosed packages take up less volume during shippingand storage compared to prior art packages. Accordingly, retailers areable to ship more packages to the end use location, thereby reducingshipping and storage costs per unit.

In addition, the disclosed packages can be produced at a lower costcompared to similar packages known and used in the art.

Further, the disclosed packages are simple in design compared to someprior art systems. Particularly, high and low oxygen gas barriercontainers known in the art are shipped in a separately maintained gasenvironment and optionally oxygen absorbers, which add an additionalprocessing step.

Although several advantages of the disclosed system are set forth indetail herein, the list is by no means limiting. Particularly, one ofordinary skill in the art would recognize that there can be severaladvantages to the disclosed system that are not included herein.

EXAMPLES

The following Examples provide illustrative embodiments. In light of thepresent disclosure and the general level of skill in the art, those ofordinary skill in the art will appreciate that the following Examplesare intended to be exemplary only and that numerous changes,modifications, and alterations can be employed without departing fromthe scope of the presently disclosed subject matter.

Example 1 Preparation of Packages 1-7

The support member of Package 1 was a thermoformed film (VC716WB,provided by Cryovac, Inc., Duncan, S.C., United States of America) withthe approximate dimensions 5 inches×7 inches×18 inches (18 mils thick),with a recessed portion sized to receive two 0.5 pound units of freshred meat. The lidding film was a 12 mil PVC film laminated to acoextruded barrier film containing PE sealant layers, an EVOH barrierlayer, and PE outer layer (available from Pack-All Inc., Melrose Park,Ill., United States of America). The surface of the lidding filmincluded a blend of antifog materials that bloomed to the film surfaceafter extrusion, which reduced the creation of condensation on the innersurface of the formed lidding film. During the packaging step, 3 or 4inwardly-facing ridges of a depth of about 0.25 inches were included onthe top and sides of the lidding film.

The meat product was then placed on the thermoformed part of the supportmember and a vacuum source was applied to remove most of the atmosphericoxygen from the package. The package was then back flushed with amixture of about 25 weight % carbon dioxide and 75 weight % nitrogengas, and the lidding film was sealed around the perimeter of the supportmember with a Multivac packaging machine (available from Multivac, Inc.,Kansas City, Mo., United States of America) using standard thermaltransfer heat sealing techniques.

Package 2 was constructed using the same method as Package 1, exceptthat the package interior was flushed with a gas mixture of 80 weight %oxygen and 20 weight % carbon dioxide prior to sealing the lidding filmto the support member.

Package 3 was constructed using the same method as in Package 1, exceptthat the package interior was flushed with a tri-gas mixture of 0.7weight % carbon monoxide gas, 20% carbon dioxide, and 79.3 weight %nitrogen gas prior to sealing the lidding film to the support member.

Package 4 was produced using the same method as Package 3, except thatthe meat was pre-treated by exposing the meat to carbon dioxide (0.7weight %) and the meat surface was observed to be bright red in color.

Package 5 was produced using the method for Package 1, with theadditional step of wrapping the entire surface of the meat with a pieceof permeable polyolefin film (Mirabella® DL150, provided by Cryovac,Inc., Duncan, S.C., United States of America) prior to placing it on thesupport member.

Package 6 was produced using the method for Package 3, with theadditional step of wrapping the meat with a piece of permeablepolyolefin film (Mirabella® DL150) prior to placing it on the supportmember.

Package 7 was produced using the method for Package 4, with theadditional step of wrapping the meat with a piece of permeablepolyolefin film (Mirabella® DL150) prior to placing it on the supportmember.

Example 2 Blooming of Packages 1-4

Packages 1-4 were incubated for 4-8 days at about 36° F. Blooming ofPackages 1, 3, and 4 was initiated by manually piercing a ⅛ inchdiameter hole into the lidding film. The blooming of the packages wasthen observed as follows:

Package 1 maintained the meat in a reduced state (purple color) untilthe package was pierced. Thereafter, the meat bloomed to a red color.

Package 2 was not pierced, but maintained a red color due to the highoxygen atmosphere within the package interior.

Package 3 maintained a bright red color over the course of therefrigeration. Upon piercing, the package maintained the bright redcolor for about 2-3 days until the meat turned a brown color.

Package 4 maintained a bright red color over the course of therefrigeration. Upon piercing, the package maintained the bright redcolor for about 2-3 days until the meat turned a brown color.

Example 3 Grease Transfer Observed with Packages 5-7

Packages 5-7 were manually inverted and shaken for about 10 seconds toallow the meat to contact the transparent lidding film. The packageswere then inspected for grease transfer to the lidding film. It wasnoted that no grease transfer was observed with Packages 5-7.

Example 4 Comparative Package 1

A Cryovac Mirabella® package (available from Sealed Air Corporation,Duncan, S.C., United States of America) consisting of a flanged tray and2-part lidding film (an inner permeable film and an outer gas barrierfilm) was provided. About 1 lb. of fresh sliced round steak was loadedonto the tray and positioned such that the meat did not project abovethe plane of the tray flange. The lidding film was hermetically sealedto the tray flange under standard conditions (i.e., at a sealingtemperature of about 135° C. and a sealing time of about 0.5 seconds). Amodified atmosphere gas mixture of 80 weight % oxygen and 20 weight %carbon dioxide was gas flushed into the package cavity and between thetwo lidding films just prior to sealing the lidding film to the trayflange. It was observed that the meat was not in contact with thelidding film in the final package configuration. The package was thenrefrigerated at about 4° C. for 5 days.

After the refrigeration, it was observed that the meat surface ofComparative Package 1 exhibited a bright red color.

Example 5 Comparative Package 2

A Cryovac Mirabella® package as in Example 4 was provided. About 1.5lbs. of fresh sliced round steak was loaded onto the tray and positionedsuch that the meat projected about 1.5 inches above the plane of thetray flange. The lidding film was then hermetically sealed to the trayflange under standard conditions with the inner permeable film in directcontact with the protruding portion of the meat. As a result, thelidding film was tented in appearance, causing the inner and outer filmsto be pressed into contact. A modified atmosphere gas mixture of 80weight % oxygen and 20 weight % carbon dioxide was gas flushed into thepackage cavity and between the two lidding film components just prior tosealing the lidding film to the tray flange. The package was thenrefrigerated at about 4° C. for 5 days.

After the refrigeration, it was observed that the meat surface ofComparative Package 2 exhibited a brown color. It is believed that themeat received insufficient oxygen resulting from the loss of atmosphericseparation between the two layers of the lidding film.

Example 6 Comparative Package 3

A Cryovac Mirabella® package as in Example 4 was provided. About 1 lb.of fresh sliced round steak was loaded onto the tray and positioned suchthat the meat projected about 0.125 inches above the plane of the trayflange. The lidding film was then hermetically sealed to the tray flangeunder standard conditions such that the inner permeable film was indirect contact with the protruding portion of the meat. A modifiedatmosphere gas mixture of 80 weight % oxygen and 20 weight % carbondioxide was gas flushed into the package cavity and between the twolidding film components just prior to sealing the lidding film to thetray flange. The package was refrigerated at about 4° C. for 5 days.

After the incubation, it was observed that the meat surface ofComparative Package 3 exhibited bright red color. It is believed thatthe volume of modified gas trapped between the two lidding films wasable to provide sufficient pressure to retain a separation.

What is claimed is:
 1. A package comprising: a. a support membercomprising a lip extending around the perimeter of the support member;and b. a thermoformed lidding film comprising: i. a flange extendingaround the perimeter of the lidding film; and ii. a dome comprising: 1.a top and sides that are interconnected to define a cavity; and
 2. aplurality of inwardly-facing ridges disposed on the dome top, sides, orboth; wherein the lidding film flange is hermetically sealed to the lipof the support member to create an enclosed space.
 2. The package ofclaim 1, further comprising an oxygen-sensitive product positioned onthe support member and within the lidding film cavity, wherein allcontact between the lidding film and the product occurs at the ridges.3. The package of claim 2, wherein the product is fresh red meat.
 4. Thepackage of claim 2, further comprising a permeable member positionedbetween the product and the lidding film.
 5. The package of claim 1,wherein the support member further comprises at least one depressionconfigured to receive a product.
 6. The package of claim 1, wherein thesupport member and the lidding film are oxygen impermeable, and thepackage further comprises at least one opening in the support member orthe lidding film, wherein the opening is covered by a removable member.7. The package of claim 1, wherein the support member and the liddingfilm are oxygen permeable, and the package is surrounded by a barrieroverwrap or a gas barrier container.
 8. The package of claim 1, whereinthe enclosed space contains a modified atmosphere comprising: a. lessthan about 0.5 weight percent oxygen; or b. at least about 50 weightpercent oxygen.
 9. The package of claim 1, wherein the support memberfurther comprises at least one inwardly-facing ridge.
 10. A method ofpackaging an oxygen-sensitive product, said method comprising: a.providing a support member comprising a lip extending around theperimeter of the support member; b. providing a thermoformed liddingfilm comprising: i. a flange extending around the perimeter of thelidding film; and ii. a dome comprising:
 1. a top and sides that areinterconnected to define a cavity; and
 2. a plurality of inwardly-facingridges disposed on the top, sides, or both; c. providing anoxygen-sensitive product; d. positioning the product on the supportmember; and e. hermetically sealing the lidding film flange to thesupport member lip such that the product is positioned within thecavity; wherein all contact between the lidding film and the productoccurs at the ridges.
 11. The method of claim 10, wherein theoxygen-sensitive product is fresh red meat.
 12. The method of claim 10,wherein the package is a modified atmosphere package with a gasconcentration in the cavity comprising: a. less than 0.5 weight percentoxygen; or b. at least 50 weight percent oxygen.
 13. The method of claim10, wherein the support member comprises at least one inwardly-facingridge.
 14. The method of claim 10, wherein the support member and thelidding film are oxygen impermeable.
 15. The method of claim 14, furthercomprising providing at least one opening in the support member orlidding film, wherein the opening is covered by a removable member. 16.The method of claim 10, wherein the support member and the lidding filmare oxygen permeable, and the method further comprises: a. enclosing thepackage within a barrier overwrap; or b. enclosing the package within agas barrier container.
 17. A method of blooming an oxygen-sensitiveproduct, said method comprising: a. providing a support membercomprising a lip extending around the perimeter of the support member;b. providing a thermoformed lidding film comprising: i. a flangeextending around the perimeter of the lidding film; and ii. a domecomprising:
 1. a top and sides that are interconnected to define acavity; and
 2. a plurality of inwardly-facing ridges disposed on thetop, sides, or both; c. providing an oxygen-sensitive product; d.positioning the product on the support member; e. inserting a desiredatmosphere into the cavity of the package prior to sealing the liddingfilm to the support member; f. hermetically sealing the lidding filmflange to the support member lip; g. either: i. wrapping the package ina barrier overwrap; ii. positioning the package within a gas barriercontainer; or iii. providing at least one opening in the support memberor the lidding film, wherein the opening is covered by a removablemember; and h. removing the overwrap, gas barrier container, orremovable member at a desired time to initiate blooming of the product;wherein all contact between the lidding film and the product occurs atthe ridges.
 18. The method of claim 17, further comprising the step ofpositioning a permeable second member between the product and thelidding film prior to sealing the lidding film to the support member.19. The method of claim 17, wherein the desired atmosphere is selectedfrom: a. less than 0.5 weight percent oxygen; or b. at least 50 weightpercent oxygen.
 20. The method of claim 17, wherein the oxygen-sensitiveproduct is red meat.